题目选项分析

Clearbell Telephone provides slow-dialing (SD) service to customers for a low fee, and fast-dialing (FD) service to other customers who pay a somewhat higher fee. FD technology, however, is so efficient that it costs Clearbell substantially less per average call to provide than does SD. Nonetheless, accountants have calculated that Clearbell's profits would drop if it provided FD to all its customers at the current low-fee rate.Assume that installation costs for FD are insignificant if the customer already has SD service.

Which of the following, if true about Clearbell, best explains the results of the accountants' calculation?

【选项】Although 96 percent of customers regard FD service as reliable and more convenient than SD, fewer than 10 percent of them choose to pay the higher fee for FD service.